Maxygen Announces Revised Record Date for Final Liquidating
Distribution

—Revised record date of June 29, 2014—

—Effective date for payment of the distribution on June 30, 2014
remains unchanged—

July 11, 2014 05:00 PM Eastern Daylight Time

NEWARK, Calif.--(BUSINESS WIRE)--Maxygen, Inc. announced today that it has revised the previously
announced record date for its final liquidating distribution in the
amount of $0.093 per share of common stock from August 29, 2013 to June
29, 2014. The effective date for payment of the distribution on June 30,
2014 remains unchanged. As previously announced, the company will make
no further distributions beyond the final liquidating distribution.
There is no requirement for stockholders to surrender shares in
connection with the final liquidating distribution.

If you hold shares of Maxygen common stock in an account with a
brokerage firm, bank or other nominee, you are encouraged to contact
your broker, bank or other nominee if you have any questions regarding
the revised record date and the payment of the distribution.